Use of a reactor stirred by a system of the archimedean screw type for the synthesis of LSX faujasite

Abstract

The performances of the industrial manufacture of LSX faujasite are improved by proceeding to the aging and the crystallization of the gel by stirring with a Archimedean screw stirrer. In particular, the duration of the aging is shortened considerably without affecting the crystallinity of the final product.

What is claimed is: 
     
       1. Method for the manufacture of low silica faujasites comprising aging and crystallizing a gel having a mole composition: Na 2  O/(Na 2  O+K 2  O): 0.7-0.8   H 2  O/Al 2  O 3  : 91-130   SiO 2  /Al 2  O 3  : 1.8-2.2   (Na 2  O+K 2  O)/Al 2  O 3  : 5.5-8   wherein during said aging and said crystallization, the gel is stirred using an Archimedean screw stirrer.   
     
     
       2. Method according to claim 1, wherein the shearing generated in the gel by the Archimedean screw is less than 25 sec -1 . 
     
     
       3. Method according to claim 1, wherein the aging takes from 10-40 h at temperatures of 30-60° C. and the crystallization from 1-5 h at temperatures of 50-100° C.